1. Field of the Invention
The present invention relates to systems for mounting modules and, more particularly, a system for mounting a pair of module boards on a mother board via sockets.
2. Description of the Related Art
There is a need for replacement of module boards in personal computers, office automation equipment, and/or communications equipment. The module boards are mounted on a mother board via sockets into or out of which the module boards are plugged. Usually, a pair of module boards are mounted on a mother board via separate sockets and interconnected by wiring on the mother board.
However, the conventional wiring conductors become very long or crisscross on the mother board.
In order to minimize the length of wiring conductors, sockets are arranged on the mother board such that the respective terminals are opposed to each other. Since the wiring between the module boards is made on the mother board, the wiring pitch is determined by the terminal pitch of the sockets so that the distance between the wiring conductors becomes too small to enhance the electrical characteristics such as impedance match.
Accordingly, it is an object of the invention to provide a module mounting system capable of minimizing the length of interconnection between module boards and enhancing the electrical characteristics such as impedance match.
According to the invention there is provided a module mounting system for interconnecting first and second module boards to a mother board having a plurality of layers, which comprises a first socket provided on a face of the mother board and having a plurality of first terminals; a second socket having a plurality of second terminals and provided on the face of the mother board such that a second rear face of the second socket is opposed to a first rear face of the first socket; and a plurality of wiring patterns provided on the layers, one for each layer, for interconnecting the first and second terminals of the first and second sockets.
It is preferred that the wiring patterns each have a plurality of wiring conductors that do not cross each other in a plane or tilted plane. The first socket comprises a first slot for receiving the first module board and supporting the first terminals in upper and lower rows and a first key provided toward an end of the first slot. The second socket comprises a second slot for receiving the second module board and supporting the second terminals in upper and lower rows and a second key provided at a position opposed to the first key. The first and second module boards are identical and each having a plurality of terminals and a key notch at positions corresponding to the first and second terminals and key; and the first and second module boards are plugged into the first and second slots in an upside down relation with each other.
The the first and second sockets are identical. The first and second slots receive the first and second module boards, respectively, and each have a plurality of first or second terminals in upper and lower rows and a first or second key toward an end of the first or second slot; the first and second module boards each have a plurality of terminals and a key notch at positions corresponding to the first or second terminals and key; the first and second module boards are plugged into the first and second slots in opposite directions.
According to another aspect of the invention there is provided a module mounting system for interconnecting first and second module boards to a mother board, which comprises a first socket provided on an upper face of the mother board and having a plurality of first terminals; a second socket provided on a lower face of the mother board and having a plurality of second terminals; interconnection means for interconnecting the first and second terminals.
The mother board has a plurality of layers and the interconnection means has a plurality of wiring patterns, one for each of the layers, to interconnect the first and second terminals. The first and second sockets are provided at corresponding positions on opposite faces of the mother board such that the wiring patterns do not cross each other in a plane. The first and second sockets are identical; first and second slots provided in the first and second sockets, respectively, for receiving the first and second module boards, respectively, and the first and second terminals, respectively, in upper and lower rows; first and second keys provided toward an end of the first and second slots, respectively; the first and second sockets are provided on the mother board in an upside down fashion with respect to each other; the first and second module boards are identical and each have a plurality of first or second terminals and a first or second key notch provided at positions correspond to the first or second terminals and key; and the first and second module boards are plugged into the first and second sockets in opposite directions.
The first socket comprises a first slot for receiving the first module board and supporting the first terminals in upper and lower rows; a first key provided toward an end of the first slot. The second socket comprises a second slot for receiving the second module board and supporting the second terminals arranged in an upside down relation with the first terminals; a second key provided toward an end of the second slot. The first and second terminals and keys are opposed to each other on opposite faces of the mother board; the first and second module boards are identical and each have a plurality of terminals and a key notch corresponding to the first or second terminals and key. The first and second terminals of the first and second sockets are opposed to each other on opposite faces of the mother board and which further comprises a plurality of wiring conductors that are perpendicular to the mother board and interconnect the first and second terminals.
With such a structure it is possible to provide the shortest wiring conductors of equal-length without any crossing to interconnect the sockets, thereby improving the electrical characteristics such as impedance match.